A. Field of the Invention
This invention relates to a pipeline pigging plug which is arranged for insertion in a pipeline and pigged to a predetermined location and then actuated to a set position to thereby create a plug in the pipeline.
B. Background of the Prior Art
There have been quite a number of tools developed for pigging through a pipeline for various purposes, including cleaning the same, magnetically searching for defects in the pipe, and even some of the pigs are arranged for blocking the pipeline to resist very low pressures.
However, none of these prior art devices have been fully satisfactory for providing a pigging device which can be moved to a predetermined location and there set to create a plug, which plug is arranged to resist extremely high fluid pressures thereagainst.
The following U.S. Pat. Nos. are generally representative of the prior art:
3,525,226 PA1 3,593,749 PA1 3,690,348 PA1 3,746,026 PA1 3,943,982 PA1 3,978,678